The present invention relates generally to ratcheting tools, and more particularly to a ratchet wrench that allows a user to easily remove an oil drain plug.
Changing the oil in a motorized vehicle requires removal of the oil drain plug so old oil can drain from the oil pan into a collection tank. In the case of businesses that specialize in fast oil change service, the oil is drained from the engine while it is still hot so that contaminants and impurities are carried out with the hot oil before having a chance to settle and cling to the bottom of the oil pan as the oil cools. Since the oil is hot, the oil plug is can be hot to the touch, making it difficult to remove. Once the oil is drained, the oil drain plug is replaced and new oil is added to the engine through an oil fill port.
Previously, the oil drain plug was removed using a variety of tools, such as an open end wrench, a fixed box end wrench, pliers, a ratcheting socket wrench or a ratcheting box end wrench. However, each tool is problematic. For example, open ends and fixed box end wrenches are slow because of the need to mount and dismount the wrench on the oil drain plug each time the wrench is indexed. Ratcheting wrenches are problematic because once the oil drain plug is broken loose, there is not enough friction between the threads of the oil drain pan and the oil plug to allow the wrench to ratchet. In any case, to quicken the process, once the drain plug is loosed the operator will usually remove the wrench and further remove the drain plug by hand.